Patients with episodic migraine with and/or without aura and chronic migraine will be treated with 100 or 200 mg of milnacipran for a total of 4 months including a one month titration phase and a 3 month maintenance phase. Baseline (pre-treatment) and end-of-maintenance phase headache frequencies will be recorded. There is no placebo treatment in this study. In addition to headache frequencies, other parameters being measured include safety and tolerability.